The number of structural and configurational isomers of a bromo compound, C5H9Br, formed by the addition of HBr to 2- pentyne respectively are

Question

The number of structural and configurational isomers of a bromo compound, C5H9Br, formed by the addition of HBr to 2- pentyne respectively are (A) 1 and 2 (B) 2 and 4 (C) 4 and 2 (D) 2 and 1

Tardigrade Admin · Accepted Answer

Addition of HBr to 2-pentyne gives two structural isomers (I) and (II). CH3 -C ≡ C-CH2CH3 xrightarrow HBr underset text(I)CH3(Br)=CHCH2CH3 underset text(II)+CH3CH=C(Br)CH2CH3 Each one of these will exist as a pair of geometrical isomers as shown below:

Thus, there are two structural and four configurational isomers.

Q. The number of structural and configurational isomers of a bromo compound, $C_{5} H_{9} B r$ , formed by the addition of $H B r$ to $2 -$ pentyne respectively are

$1$ and $2$

$2$ and $4$

$4$ and $2$

$2$ and $1$

Q. The number of structural and configurational isomers of a bromo compound, C5​H9​Br, formed by the addition of HBr to 2− pentyne respectively are

1 and 2

2 and 4

4 and 2

2 and 1

Q. The number of structural and configurational isomers of a bromo compound, $C_{5} H_{9} B r$ , formed by the addition of $H B r$ to $2 -$ pentyne respectively are

$1$ and $2$

$2$ and $4$

$4$ and $2$

$2$ and $1$